The first totalsynthesis of (±)-(Z)-9-(bromomethylene)-1,5,5-trimethylspiro[5.5]undeca-1,7-dien-3-one, a chamigrane sesquiterpene having a novel bromomethylene group is described.
作者:Guo, Ping、Song, Xuedong、Huang, Banruo、Zhang, Ruixue、Zhao, Jie
DOI:10.1002/anie.202405449
日期:——
Photoinduced zirconocene catalysis was utilized to achieve the reductivecoupling of ethers with remarkable activity and cross-selectivity. Mechanistic investigation revealed that photoexcitation of low-valent zirconocene facilitates the scission of benzylic C(sp3)−O bonds, resulting in benzylic radicals that recombine with Zr center. Subsequent carbomagnesiation generates benzylic Grignard reagents
(+/-)-(Z)-9-(Bromomethylene)-1,5,5-trimethylspirol[5.5]undeca-1,7-dien-3-one (1), a chamigrane sesquiterpene having a novel bromomethylene group is synthesized from anisole via spiroannelation of 4-(1,1-dimethyl-4-formylbutyl)-3-cyclohexen-1-one (10).